He’s magnetic as few people are, well titled, brilliant, a poetic genius, utterly debauched, and what would today be called manic-depressive. Her parents try to warn her, but Anne Isabella (Annabella) Milbanke, Baroness of Wentworth, will have her Lord Byron, believing that ardent love and a spotless moral example will cure him of his excesses. It’s 1815, the year of Waterloo, and a different sort of battle is about to begin.

Annabella’s delusion receives a sharp setback on her wedding day, and though the Byrons pass a few companionable weeks, during which Annabella becomes pregnant, their marriage quickly falls apart. Lord Byron prefers other women, especially his half-sister, Augusta, and only someone as innocent as Annabella could have failed to realize how deep that preference runs. By the time Annabella’s daughter is born, and he insists on naming her Augusta, as is his legal right, his long-suffering wife begins to get the idea. Shortly afterward, Annabella leaves Byron, a scandal so infamous the separation is forever referred to with a capital S. Henceforth, she calls her daughter only by her middle name, Ada, and sets out to eradicate any presence of her former husband, real or perceived. She decides that an overwrought imagination led to Byron’s depravity, and she watches her young child for that or any other evidence of “evil Byron blood.” Whenever Ada shows the least sign of willfulness, subversion, or curiosity deemed repugnant, Annabella leaves home, putting Ada in the hands of hirelings who enjoy correcting her every fault, many of which exist only in their eyes, and determined that no fairytales, flights of fancy, or moments spent ruminating ever be part of this young girl’s life.

I confess I have a visceral reaction to this novel, which could be subtitled How to Destroy a Child. I wanted to rescue this poor girl from parental tyranny and show her kindness, warmth, and encouragement. However, the stakes are even higher than that of an emotionally strangled child, for Ada is preternaturally intelligent, passionate about science, and a born mathematician. Luckily, Annabella tolerates this to some extent, or the world would have lost a genius. Known to history as Ada Lovelace, Lord Byron’s only legitimate child has been credited by some historians as having devised the first computer algorithm, in a journal article discussing the work of her close friend, Charles Babbage. But, as Chiaverini tells it, all this could have easily gone another way.

How this comes to be shapes the narrative, but Enchantress of Numbers is much more than a biographical novel, a genre that too often shows its limitations. Chiaverini succeeds brilliantly, in part because each chapter has its “no — and furthermore” and portrays Ada’s struggles lucidly. She longs to make her own decisions, and, as she gets older, to gain recognition for her science, not as an ornament to her father’s misbegotten reputation. Even better, Chiaverini carries these conflicts through Ada’s adulthood, and they never recede. Her mother remains withholding, elusive, and controlling; and men are men, with rights and privileges Ada can never claim. Moreover, though Ada counts among her friends such luminaries as Darwin, Dickens, Faraday, and Mary Somerville (Ada’s mentor, a brilliant polymath for whom a college at Oxford is now named), most scientists dismiss her work as dabbling, simply because she’s a woman. No doubt Countess Lovelace would have understood implicitly the endemic sexism in today’s Silicon Valley and have much to say about it.

But feminism aside, Enchantress of Numbers is also about a corrosive mother-daughter relationship and the rivalries that Annabella exploits for her own advantage. No question that Byron abused her, and since his subsequent poems satirize her mercilessly, she continues to suffer. But she passes on the punishment with interest, constricting Ada within an inch of her life while not letting her read the poems, so that the girl’s only knowledge of her father comes from her mother’s harangues. Even his family portrait is hidden in her grandparents’ house:

Whenever I was feeling especially brave, I would steal into the room alone and gaze up at the covered portrait, wondering what lay behind the dark green curtain. What did my father look like? Of course I did not remember . . . . There must be something truly terrible about his appearance or my grandmother would not have hidden him from view. . . . In my imagination — that wicked, persistent faculty — he became a chimera of the magnificent and the monstrous. . . . and . . . Since I was his child, something sinister and dangerous lurked within me too.

I wish that Chiaverini had devoted more space to Ada’s emotional reckonings late in her short life, though I understand why the author didn’t go that way. Enchantress of Numbers is lengthy as it is. But it’s utterly riveting as well as topical, and I highly recommend it.

Disclaimer: I obtained my reading copy of this book from the public library.